Imagery, sediment collection, photogrammetry, and meteorological data from July 2023 to November 2024, Grand Falls Dune Field, Arizona

Grand Falls dune field (GFDF) is located on the Navajo Nation, ~70 km NE of Flagstaff, AZ. This active dune field displays a range of morphologies, including barchans, dome dunes, smaller dunes, and ripples, and is bimodal both in mineralogical composition and grain size distribution. The felsic component is likely derived from the Little Colorado River, and the mafic component (basaltic grains) is locally sourced from nearby cinder cones [1]. GFDF is an excellent analog site for both active dunes on Mars and other planetary bodies that have dune-like features (e.g., Venus and Titan). At this active site we have deployed a meteorological station (recording temperature, barometric pressure, relative humidity, wind direction, wind speed, solar radiation, and precipitation every 15 minutes during the windy season and every hour during the calmer months), three sets of five Big Spring Number Eight (BSNE) and two sets of six Modified Wilson and Cook (MWAC) passive sediment samplers, and three game trail cameras (we used BlazeVideo game cameras from July 2023 to July 2024, and Browning game trail cameras from July 2024 to November 2024). Cameras were set up around an active ripple site, taking images every ten minutes to record sand movement close to the surface. During each visit to the field site, we imaged active ripples using a NIKON D750 DSLR camera. Using Agisoft Metashape Professional, we processed the images to create digital elevation models of the ripple field. Sediment collected by passive samplers was retrieved approximately every two weeks during the windy season to study saltation and quantify sediment flux. Data presented here span from July 2023 to November 2024.

[1] Hayward, R. K. et al. (2010) 2nd Int. Plan. Dunes Wrkshp., Abstract #2004.

Fieldwork on the Navajo Nation was conducted under a permit from the Navajo Nation Minerals Department. Any persons wishing to conduct geologic investigations on the Navajo Nation must first apply for and receive a permit from the Navajo Nation Minerals Department, P.O. Box 1910, Window Rock, Arizona 86515, and telephone # (928) 871-6587.